package net.xdclass.utils;

import javax.servlet.http.HttpServletRequest;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.security.MessageDigest;

public class CommonUtil {
    /**
     * 获取ip
     *
     * @param request
     * @return
     */
    public static String getIpAddr(HttpServletRequest request){
        String ipAddress=null;
        try{
            ipAddress=request.getHeader("x-forwarded-for");
            if(ipAddress==null||ipAddress.length()==0||"unknown".equalsIgnoreCase(ipAddress)){
                ipAddress=request.getHeader("Proxy-Client-IP");
            }
            if(ipAddress==null||ipAddress.length()==0||"unknown".equalsIgnoreCase(ipAddress)){
                ipAddress=request.getHeader("WL-Proxy-Client-IP");
            }
            if(ipAddress==null||ipAddress.length()==0||"unknown".equalsIgnoreCase(ipAddress)){
                ipAddress=request.getRemoteAddr();
                if(ipAddress.equals("127.0.0.1")){
                    // 根据网卡取本机配置的IP
                    InetAddress inet=null;
                    try{
                        inet=InetAddress.getLocalHost();
                    }catch(UnknownHostException e){
                        e.printStackTrace();
                    }
                    ipAddress=inet.getHostAddress();
                }
            }
            // 对于通过多个代理的情况，第一个IP为客户端真实IP,多个IP按照','分割
            if(ipAddress!=null&&ipAddress.length()>15){
                // "***.***.***.***".length()
                // = 15
                if(ipAddress.indexOf(",")>0){
                    ipAddress=ipAddress.substring(0,ipAddress.indexOf(","));
                }
            }
        }catch(Exception e){
            ipAddress="";
        }
        return ipAddress;
    }


    public static String MD5(String data){
        try{
            java.security.MessageDigest md= MessageDigest.getInstance("MD5");
            byte[]array=md.digest(data.getBytes("UTF-8"));
            StringBuilder sb=new StringBuilder();
            for(byte item:array){
                sb.append(Integer.toHexString((item&0xFF)|0x100).substring(1,3));
            }

            return sb.toString().toUpperCase();
        }catch(Exception exception){
        }
        return null;

    }
}
